Exposure to extreme heat is the reality of unit preparation for operational missions. Many heat injuries are preventable, and none need be fatal. Leaders must assess unit's missions and training requirements against the risk associated with operating in warm weather environments. Early recognition and treatment of Soldiers presenting with symptoms of heat injuries are key to saving lives.

Exertional Heat Illness ("EHI") refers to a spectrum of disorders (e.g., cramps, heat exhaustion, heat injury, heat stroke) resulting from total body heat stress. While there is a range of adverse effects that can result from the body over-heating, the 2 major kinds of heat illnesses that are referred to as heat casualties are: forms of heat exhaustion (can be milder or more severe), while more severe cases are heat stroke(most severe form of heat illness and possibly fatal).

HEAT EXHAUSTION

“Canaries in the coal mine” - need to catch these before they get to a more extreme case of heat stroke - catch early as they need rest/water/evaluation and possible medical care.

Symptoms:

ØDizziness

ØHeadache

ØNausea

ØWeakness

ØClumsy/unsteady walk

ØMuscle cramps

Treatment:

ØRest Soldier in shade

ØLoosen uniform/remove head gear

ØHave Soldier drink 2 quarts of water over 1 hour

ØEvacuate if no improvement in 30 minutes, or if Soldier's condition worsens

HEAT STROKE

Medical emergency – these cases already have abnormal brain function and can be fatal – initiaterapid cooling and EVAC!

Symptoms:

ØProfuse sweating

ØConvulsions and chills

ØVomiting

ØConfusion, mumbling - do mental check questions to see if brain is working correctly

ØCombative

ØPassing out (unconscious)

Treatment:

ØCOOL and CALL!! – the faster the body is cooled, the less damage to the brain and organs

ØStrip (if possible, ensure a same gender helper is present)

ØRapid cool (ice sheets)

§Cover all but face with iced sheets.

§Ensure the iced sheet is soaked prior to applying to the casualty.

§Fan the entire body.

§Stop cooling if victim starts shivering.

ØCall for evacuation

ØContinue cooling during transport

ØNOTE: The same person should observe the Soldier during cooling and evacuation in order to spot symptom changes.

HYPONATREMIA "Water Intoxication"

This is a Medical Emergency – EVAC immediately, can be mistaken for Heat Stroke, though treatment is very different. NOTE: condition most often occurs in TRADOC IET units, especially during BCT/OSUT.

Symptoms:

ØMental status changes

ØVomiting

ØHistory of consumption of large volume of water

ØPoor food intake

ØAbdomen distended/bloated

ØLarge amounts of clear urine (if urine)

Treatment:

ØDo not give more water or IV! If awake, allow Soldier to consume salty foods or snacks

ØEvacuate immediately

REACTING TO A HEAT ILLNESS CASUALTY:

Remember "M.A.D.E. in the Shade":

MOVE victim to cool location (e.g., shade, A/C car, building)

ASSESS victim to determine type of EHI

- Signs/symptoms

- Hydration (550 cord)to check for hyponatremia

-

Risk level (red beads or riskfactors)

- Mental status (for heat stroke)

- Designate single person to continue monitoring. It is critical that a specific person is assigned to STAY with victim and continuously monitor all changes including mental status – Even the slightest changes that can occur in minutes may not be noticed if different personnel are checking victim – these slight changes can be critical in ensuring the best outcome for the victim.

DECIDE which EHI and take proper management approach

- Heat Exhaustion: rest in shade, rehydrate

- Heat Stroke: begin rapid cooling, evacuate immediately

-

Hyponatremia: evacuate immediately

EVALUATE other Soldiers and adjust training as necessary

WET BULB GLOBE TEMPERATURE

Wet Bulb Globe Temperature (WBGT) is a composite temperature used to estimate the effect of temperature, humidity, wind speed(‘wind chill’), and visible and infrared radiation (e.g., sunlight) on humans. The WBGT index was developed in 1956 by the United States Marine Corps at Parris Island to reduce heat stress injuries in recruits.It is determined with special equipment and calculated to reflect components of air, humidity and wind that affect ‘actual temperature’ experienced by personnel: WBGT is derived from the formula: 0.7Tw + 0.2Tg + 0.1Td

- Highly motivated - the desire to meet or exceed standards may lead some Soldiers to continue to push themselves as early signs/symptoms of EHI occur. These Soldiers should not be discouraged from pushing themselves but cadre should be aware of their tendency so that they can be watched more closely.

FIVE STEPS OF RISK MANAGEMENT TO PREVENT EHI

1. IDENTIFY THE HAZARDS:

Know the Wet Bulb Globe Temperature (WBGT)

Know the Total Body Heat Stress = Total Heat Load on an invidivual =

1) Heat generated by the body (due to metabolism and activity)

2) +Heat gained from the environment

3) -Heat lost in the environment

Know the Risk Factors for EHI. Most commonly thought of risk factors are the climate/temperature and the level of physical activity/exertion, however there are numerous individual risk factors to be aware of - especially consider when a single individual has more than one of the listed risk factors.

2. ASSESS HAZARDS:

Utilize the WBGT temperature index

- Add 5°F for rucksack or body armor

- Add 10°F if in MOPP 4

Know your Soldiers- Identify individuals at increased risk

Monitor hydration status- Assess morning and evening as well as during training

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